Browsers, if anything, are the greatest paradox within computer programs. As much as people need them to obtain information (compare clicking a link to using 'wget' or 'curl'), they are the easiest doors to be exploited by attackers, and resource-heavy by comparison. However, browsers do evolve with these issues, and are constantly working on them - except that savvy users are never really satisfied. So one of the key terms for Browsers today is the concept of "lightweight." Every modern browser available for download today refers to itself as lightweight. The only problem is that nobody knows its exact definition.
Firefox and Chrome(-ium) are both decent browsers in my opinion, and call themselves light. In truth, however, they support everything you can think of. The outcome is the standard recipe web-browser which takes a good 100MB off the RAM to run your favorite page, and a couple more to load a full browsing session. This may be adequate to you, provided you have the memory to spend, but it's kind of a waste to burn this much just to view a few tabs of content just to search something in Google. Hence, a lightweight browser isn't enough. It's time to dig for something deeper, a
featherweight browser.